A comparison of 4-year entecavir efficacy in nucleos(t)ide analog-naïve and -experienced adult Taiwanese chronic hepatitis B patients

HBV relapse rates in patients who discontinue tenofovir disoproxil fumarate with or without switching to tenofovir alafenamide

BACKGROUND/AIMS

The incidence and relapse pattern in patients stopping tenofovir alafenamide (TAF), a prodrug of tenofovir which is more concentrated in hepatocytes, is unknown.

METHODS

HBeAg-negative CHB patients stopping tenofovir disoproxil fumarate (TDF) (off-TDF) or who had switched to TAF more than 3 months before discontinuation (off-TAF) were recruited. The propensity score-matching method (PSM) was used, creating a ratio of 1:3 between the off-TAF versus the off-TDF groups to adjust for associated factors.

RESULTS

After PSM, 180 off-TDF and 60 off-TAF patients were analyzed. The cumulative rates of virological and clinical relapse at 52 weeks were 75.1% and 58.5% respectively in the off-TDF group and 91.1% and 61.6% in the off-TAF group. Patients in the off-TAF group had significantly higher rates of virological relapse than those in the off-TDF group (p = 0.021), but not clinical relapse (p = 0.785). Multivariate cox regression analysis showed that off-TAF group was an independent factor for virological relapse, but not clinical relapse. Severity of clinical relapse and hepatic decompensation rate were comparable between off-TDF and off-TAF groups CONCLUSIONS: The off-TAF group had a higher virological relapse rate than the off-TDF group. The difference in clinical relapse pattern and severity was not clinically important between the two groups.

Kinetics in HBsAg after Stopping Entecavir or Tenofovir in Patients with Virological Relapse but Not Clinical Relapse

This study investigated the kinetics in HBsAg and the HBsAg loss rate after entecavir or tenofovir disoproxil fumarate (TDF) cessation in patients with chronic hepatitis B (CHB) who achieved virological suppression after virological relapse without clinical relapse. A total 504 HBeAg-negative, non-cirrhotic patients who previously received entecavir or TDF with post-treatment and who were followed up for at least 30 months were included. Of the 504 patients, 128 achieved sustained virological suppression (Group I), and 81 experienced virological relapse without clinical relapse. Of the 81 patients, 52 had intermittent or persistent HBV DNA > 2000 IU/mL (Group II), and 29 achieved persistent virological suppression (HBV DNA < 2000 IU/mL) for at least 1.5 years (Group III) after virological relapse. A generalized estimating equations analysis showed that Groups I and III experienced larger off-treatment HBsAg declines than Group II (both, p < 0.001). The post-treatment HBsAg declines of Group I and Group III were similar (p = 0.414). A multivariate analysis showed that there were no differences in the HBsAg change and HBsAg decline (p = 0.920 and 0.886, respectively) or HBsAg loss rate (p = 0.192) between Group I and Group III. The patients who achieved persistent viral suppression after HBV relapse without clinical relapse have a similar decline in HBsAg and the HBsAg loss rate as the sustained responders.

The Impact of Nucleos(t)ide Analogs Off-Therapy Among Chronic Hepatitis B Patients: A Systematic Review and Meta-Analysis

Background and Aim: Although most chronic hepatitis B (CHB) patients achieve effective virological suppression after receiving long-term nucleos(t)ide analogs (Nucs) therapy, the safety of off-therapy is controversial under the monitor.

Methods: We identified studies through searching PubMed, Embase, Cochrane Library, and Web of Science from January 1990 to February 2021. The eligible studies compare the long outcomes between discontinued and continued Nucs treatments groups among CHB patients. This study was conducted to investigate long-term outcomes, including biochemical, serological, and virological outcomes, as well as hepatocellular carcinoma (HCC) development rate between discontinued and maintained Nucs therapy groups among CHB patients.

Results: Five eligible studies covering 1,425 patients were selected for meta-analysis. Our result exhibits that patients with Nucs off-treatment have a higher risk of alanine aminotransferase (ALT) flares-up than those who continued Nucs therapy under the monitor (OR = 9.39, 95%CI = 3.87–22.78). Nucs off-therapy patients have a higher virological bound incidence (OR = 617.96, 95%CI = 112.48–3,395.14) and a higher HBV DNA level (OR = 9.39, 95%CI = 3.87–22.78) than those who continued Nucs therapy. There was no statistically significant difference in the risk of hyperbilirubinaemia, hepatic decompensation, and HCC development between both two groups. Patients in Nucs off-therapy group demonstrate a higher HBsAg loss rate than those in the continued group (OR = 7.10, 95%CI = 6.68–13.69).

Conclusions: Nucs off-therapy patients may exhibit a higher chance of achieving HBsAg loss than those who continue Nucs therapy. It requires close monitoring after Nucs off-therapy and timely restarting of Nucs therapy when ALT concentrations increase.

The role of hepatitis B virus core-related antigen in predicting hepatitis B virus relapse after cessation of entecavir in hepatitis B e antigen-negative patients

This study investigated the ability of hepatitis B core-related antigen (HBcrAg) to predict hepatitis B virus (HBV) relapse in HBeAg-negative patients after cessation of entecavir therapy. A total of 301 HBeAg-negative patients without cirrhosis who had stopped entecavir therapy for at least 12 months were recruited. All patients fulfilled the stopping criteria proposed by the APASL 2012 guidelines. The five-year cumulative rates of virological relapse, clinical relapse and HBsAg loss were 71.6%, 57.3% and 18.7%, respectively. Serum HBsAg at end of treatment (EOT) was an independent predictor of virological relapse, clinical relapse and HBsAg loss; an EOT HBsAg of 150 IU/ml was the optimal cut-off value. The 5-year virological relapse rates for patients with <150 and ≥150 IU/ml HBsAg at EOT were 43.3% and 82.2% (p < 0.001), clinical relapse rates were 32.3% and 66.3% (p < 0.001), and HBsAg loss rates were 46.1% and 5.2% (p < 0.001), respectively. A baseline HBcrAg of 4 IU/ml was the optimal cut-off value for predicting HBV relapse. Among patients with an EOT HBsAg <150 IU/ml, the five-year virological relapse rates for patients with baseline HBcrAg levels ≤4 and >4 log U/ml were 27.9% and 59.1% (p = 0.006) and the clinical relapse rates were 18% and 48.1% (p = 0.014), respectively. EOT HBcrAg was not a significant predictor of virological or clinical relapse after cessation of entecavir. In conclusion, the combination of an EOT HBsAg of 150 IU/ml and baseline HBcrAg of 4 log U/ml can effectively predict the risk of HBV relapse after stopping entecavir therapy.

Associations of HBV Genotype B vs C Infection With Relapse After Cessation of Entecavir or Tenofovir Therapy

BACKGROUND & AIMS

We compared rates of relapse of hepatitis B virus (HBV) infection between patients with HBV genotype B vs genotype C infection after cessation of entecavir or tenofovir disoproxil fumarate (TDF) therapy. All patients included in the study were HB e antigen (HBeAg)-negative.

METHODS

We performed a retrospective study of 460 HBeAg-negative patients without cirrhosis in Taiwan who had stopped entecavir or TDF treatment for at least 12 months; data were collected from 2007 through 2016. All patients fulfilled the stopping criteria proposed by the APASL 2012 guidelines. Patients were evaluated every 1-3 months during the first 6 months after stopping therapy and then every 3 months until their last hospital visit; HB surface antigen (HBsAg) was measured in serum samples collected before treatment, after 12 months of treatment, and at the end of treatment. Virologic relapse was defined as a serum level of HBV DNA >2000 IU/mL after the cessation of treatment; clinical relapse was defined as increase in alanine aminotransferase more than 2-fold the upper limit of normal (40 U/L) and level of HBV DNA >2000 IU/mL after stopping treatment.

RESULTS

Significantly higher proportions of patients with HBV genotype B infection had virologic and clinical relapse and retreatment than patients with HBV genotype C infection, among all patients and among patients matched by propensity sore. Patients who discontinued TDF therapy had significantly higher rates and earlier times of virologic and clinical relapse than patients who discontinued entecavir therapy, among all patients and propensity score-matched patients. Multivariate analysis showed that TDF therapy, old age, HBV genotype B, and higher end of treatment HBsAg level were independently associated with virologic and clinical relapse. Five-year rates of virologic and clinical relapse were low (19.2% and 15.4%, respectively) in patients with a combination of end of treatment level of HBsAg of 100 IU/mL or less and HBV genotype C infection. Rates of off-therapy HBsAg loss, development of hepatocellular carcinoma, and hepatic decompensation did not differ significantly between patients with HBV genotypes B vs C infection or between the entecavir vs TDF groups.

CONCLUSIONS

Higher proportions of HBeAg-negative patients with HBV genotype B infection have virologic and clinical relapse and retreatment than patients with HBV genotype C infection, after cessation of entecavir or TDF therapy.

Incidence and Factors Associated With HBV Relapse After Cessation of Entecavir or Tenofovir in Patients With HBsAg Below 100 IU/mL

BACKGROUND & AIMS

We investigated the incidence and factors associated with relapse of hepatitis B virus (HBV) infection in patients with levels of HB surface antigen (HBsAg) less than 100 IU/mL after cessation of entecavir or tenofovir disoproxil fumarate (TDF) treatment.

METHODS

We collected data from patients with chronic HBV infection without cirrhosis treated with entecavir from 2007 through 2015 or TDF from 2011 through 2016 in Taiwan. We identified 135 patients with levels of HBsAg less than 100 IU/mL at the end of treatment (79 entecavir and 56 TDF) and collected data from them for a median of 87 weeks (interquartile range, 48-161 wk) for use as the development set. We collected data from 108 patients from separate medical centers in Taiwan, followed up for a median of 126 weeks (interquartile range, 61-214 wk), and used these as the validation group. Post-treatment virologic relapse was defined as a serum HBV DNA level greater than 2000 IU/mL, and clinical relapse was defined as an alanine aminotransferase level greater than 80 U/L and a HBV DNA level greater than 2000 IU/mL.

RESULTS

In the development group, the 5-year incidences of virologic relapse, clinical relapse, and HBsAg loss were 40.9%, 32.5%, and 47%, respectively. The baseline HBV DNA and end-of-treatment levels of HBsAg were associated independently with relapse. In the development group, 17.3% of patients with end-of-treatment HBsAg levels less than 40 IU/mL had a virologic relapse within 5 years, whereas 67.6% of patients with a HBsAg level of 40 IU/mL or more had a virologic relapse within 5 years (P < .001); proportions of patients with clinical relapses were 10.2% (HBsAg <40 IU/mL) and 57.6% (HBsAg ≥40 IU/mL; P < .001). In the validation groups, for patients with end-of-treatment HBsAg levels less than 40 IU/mL or 40 IU/mL or more, the rates of virologic relapse at 5 years were 31.1% and 80.5% (P < .001), and rates of clinical relapse were 14.2% and 50.3% (P < .001), respectively. Rates of virologic and clinical relapse within 5 years were low (<10%) in patients with a combination of end-of-treatment HBsAg level less than 40 IU/mL and baseline HBV DNA level less than 5 × 10⁴ IU/mL, or baseline hepatitis B core-related antigen level less than 4 log U/mL in the development group.

CONCLUSIONS

An end-of-treatment HBsAg level of 40 IU/mL or less is optimal for stopping nucleos(t)ide analog therapy. Waiting to stop therapy until patients have a combination of baseline HBV DNA level of 5 × 10⁴ IU/mL or hepatitis B core-related antigen of 4 log U/mL and end-of-treatment HBsAg level of 40 IU/mL might reduce the risk of HBV relapse.

The Incidence of Hepatitis B Surface Antigen Loss Between Hepatitis B E Antigen-Negative Noncirrhotic Patients Who Discontinued or Continued Entecavir Therapy

BACKGROUND

We compared rates of hepatitis B surface antigen (HBsAg) loss and hepatocellular carcinoma (HCC) development in hepatitis B e antigen (HBeAg)-negative patients without cirrhosis who continued or discontinued entecavir.

METHODS

Patients who discontinued entecavir treatment for at least 12 months (discontinued group; n = 234) and patients who continued entecavir treatment for at least 4 years (continued group; n = 226) were recruited.

RESULTS

In the discontinued group, the 5-year cumulative incidences of virological relapse (VR), clinical relapse (CR), and HBsAg loss were 71.9%, 58.9%, and 13%, respectively. Patients with sustained response, VR but no CR, and CR without retreatment were 49-, 13-, and 18-fold more likely to develop HBsAg loss than those with retreatment. Patients who discontinued entecavir therapy had a higher rate of HBsAg loss than those who continued entecavir therapy, in all and 360 propensity score (PS)-matched patients. Cox regression analysis revealed that the discontinued group was an independent predictor for HBsAg loss. There was no significant difference in HCC development between the 2 groups in all and PS-matched patients.

CONCLUSIONS

HBeAg-negative patients without cirrhosis who discontinued entecavir treatment exhibited a higher HBsAg loss rate without an increased risk of HCC compared to those who continued entecavir treatment.

Effectiveness and safety of switching to entecavir hepatitis B patients developing kidney dysfunction during tenofovir

BACKGROUND AND AIMS

Tenofovir disoproxil fumarate (TDF) is recommended for chronic hepatitis B (CHB) treatment, but it may induce kidney dysfunction whose management is not yet known. This Italian, multicentre, retrospective study aimed to assess the efficacy and safety of switching to entecavir (ETV) patients who developed TDF-associated glomerular and/or tubular dysfunction.

METHODS

A total of 103 TDF-treated patients were included as follows: age 64 years, 83% male, 49% cirrhotics, 98% with undetectable HBV DNA, 47% with previous lamivudine resistance (LMV-R) and 71% previously treated with adefovir. Twenty-nine (28%) were switched to ETV because estimated glomerular filtration rate (eGFR_MDRD ) was <60 mL/min, 37 (36%) because blood phosphate (P) levels were <2.5 mg/dL and 37 (36%) for both reasons. Kidney, liver and virological parameters were recorded every 4 months thereafter.

RESULTS

During 46 (4-115) months of ETV treatment, all patients' renal parameters significantly improved as follows: creatinine from 1.30 to 1.10 mg/dL (P < 0.0001), eGFR_MDRD from 54 to 65 mL/min (P = 0.002), P from 2.2 to 2.6 mg/dL (P < 0.0001) and maximal tubule phosphate reabsorption (TmPO4/eGFR) from 0.47 to 0.62 mmol/L (P < 0.0001). Thirteen patients (52%) improved their eGFR_MDRD class, P levels were normalised in 13 (35%), and eight (22%) showed improvements in both parameters. Viral suppression was maintained in all but five patients (5%), all of whom had been LMV-R. The 5-year cumulative probability of ETV-R was 0% in LMV-naïve patients, and 11% in LMV-R patients (P = 0.018).

CONCLUSIONS

Entecavir is an effective and safe rescue strategy for CHB patients who develop renal dysfunction during long-term TDF treatment.

Taiwan consensus statement on the management of chronic hepatitis B

The experts of Taiwan Association for the Study of Liver (TASL) have actively participated and led the guidelines on hepatitis B virus (HBV) management by Asian Pacific Association for the Study of Liver (APASL) which is the first international association for the study of liver to publish the statement on HBV management before. However, there are more and more new data on the natural history and treatment of HBV infection in the past decade. These include new application of an old biomarker (quantitative HBsAg), clinical significance of HBV genotype and naturally occurring mutations, the role of non-invasive examination in evaluating severity of hepatic fibrosis, clinical significance of outcome calculators, new drug or new combination strategies towards more effective therapy and organ transplantation including liver and non-liver transplantation. It is time to publish the guidelines on HBV management of Taiwan. Hence, TASL have conducted an expert meeting to review, to discuss and to debate the relevant literatures, followed by draft the manuscript of HBV management guidelines and recommendations. The guidelines include general management, indications for fibrosis assessment, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patient receiving immune suppression or chemotherapy and patients in the setting of liver transplantation and hepatocellular carcinoma, are also included.

Long-term incidence and predictors of hepatitis B surface antigen loss after discontinuing nucleoside analogues in noncirrhotic chronic hepatitis B patients

OBJECTIVE

To investigate the long-term incidence and predictors for hepatitis B surface antigen (HBsAg) loss after nucleoside analogue therapy.

METHODS

The study included 411 noncirrhotic chronic hepatitis B patients (148 hepatitis B e antigen (HBeAg)-positive and 263 HBeAg-negative patients) who were treated with lamivudine (n = 110) or entecavir (n = 301) with posttreatment follow-up of at least 12 months.

RESULTS

In HBeAg-positive patients, the 8-year cumulative rates of virologic relapse, clinical relapse and HBsAg loss were 55.6%, 47.7% and 19.6%, respectively. In HBeAg-negative patients, the rates were 69.3%, 58.9% and 33.1%, respectively. Cox regression analysis showed that hepatitis B virus genotype C and lower end-of-treatment HBsAg levels were independent predictors of HBsAg loss in HBeAg-positive and -negative patients. The 5-year HBsAg loss rate was 47.3% in HBeAg-positive patients with end-of-treatment HBsAg levels <300 IU/mL, while the 8-year HBsAg loss rate was 69.3% in HBeAg-negative patients with end-of-treatment HBsAg levels <200 IU/mL. Five patients experienced hepatitis flares with decompensation after stopping nucleoside analogue therapy, and one died after retreatment. Of the 48 patients who developed off-therapy HBsAg loss, two developed hepatocellular carcinoma.

CONCLUSIONS

The rate of HBsAg loss was relatively high and the rate of hepatic events was low in noncirrhotic patients who discontinued nucleoside analogue therapy.

Hepatitis B surface antigen loss and clinical outcomes between HBeAg-negative cirrhosis patients who discontinued or continued nucleoside analogue therapy

We investigated the incidence and predictors of post-treatment hepatitis B virus (HBV) relapse and hepatitis B surface antigen (HBsAg) loss. After cessation of nucleoside analogue (NA) treatment in hepatitis B e antigen (HBeAg)-negative patients with cirrhosis. The rates of HBsAg loss and hepatocellular carcinoma (HCC) development in HBeAg-negative patients with cirrhosis who continued NA treatment were compared with those who discontinued treatment. Patients with compensated cirrhosis who had discontinued NA treatment for at least 12 months (discontinuing group; n=73) and patients who continued entecavir treatment for at least 4 years (continuing group; n=158) were recruited. Serum HBsAg levels were analysed at the end of treatment (discontinuing group) or at 2.5-3 years of treatment (continuing group). In the discontinuing group, the 6-year cumulative incidence of post-treatment virological relapse and HBsAg loss were 56.3% and 46.7%, respectively. The end-of-treatment HBsAg level of 300 IU/mL was a cut-off value for subsequent post-treatment HBsAg loss and sustained response. In the continuing group, HBsAg loss occurred in five of 158 patients. Cox regression analysis showed that HBsAg levels in the discontinuing group were independent predictors for HBsAg loss in all patients and 104 propensity score (PS)-matched patients. There was no significant difference in HCC development between the groups in all patients and 104 PS-matched patients. Two patients experienced post-treatment alanine aminotransferase flare with hepatic decompensation, and neither of them died after retreatment. In conclusion, HBeAg-negative patients with cirrhosis who discontinued NA treatment might have a higher rate of HBsAg loss and their risk of developing HCC did not increase compared with those who continued entecavir treatment.

Incidence and predictors of HBV relapse after cessation of nucleoside analogues in HBeAg-negative patients with HBsAg ≤ 200 IU/mL

The predictors of hepatitis B virus (HBV) relapse and HBsAg loss after cessation of nucleos(t)ide analogues (NA) in HBeAg-negative patients with end-of-treatment HBsAg ≤ 200 IU/mL remains unclear. The study recruited 119 chronic hepatitis B (CHB) patients who achieved end-of-treatment HBsAg ≤ 200 IU/mL, were treated with lamivudine (n = 34) and entecavir (n = 85). The 5-year rates of post-treatment virological relapse, clinical relapse, and HBsAg loss at 60 months were 39.4%, 27.6%, and 45.9%, respectively. Cox regression analysis revealed that HBV DNA at entry and end-of-treatment HBsAg levels were independent predictors of virolgical and clinical relapse. HBV genotype C and end-of-treatment HBsAg were independent factors of HBsAg loss. Patients with a combination of end-of-treatment HBsAg < 50 IU/mL and HBV DNA < 2 × 10⁵ IU/mL at entry experienced the lowest virological and clinical relapse rates (5% and 0% at 60 months, respectively). In contract, patients with a combination of end-of-treatment HBsAg ≥ 50 IU/mL and HBV DNA ≥ 2 × 10⁵ IU/mL at entry experienced high virological and clinical relapse (80.7% and 71.5% at 60 months, respectively). No patients experienced hepatic decompensation when clinical relapse occurred after timely retreatment. A combination of HBV DNA levels at entry and end-of-treatment HBsAg levels was useful for predicting the post-treatment HBV relapse in HBeAg-negative patients with HBsAg ≤ 200 IU/mL.

Association Between Level of Hepatitis B Surface Antigen and Relapse After Entecavir Therapy for Chronic Hepatitis B Virus Infection

BACKGROUND & AIMS

We investigated the rate of relapse of hepatitis B virus (HBV) infection after entecavir therapy for chronic hepatitis B and the association between level of hepatitis B surface antigen (HBsAg) and relapse.

METHODS

In a retrospective study, we analyzed data from 252 patients with chronic HBV infection who were treated with entecavir and met the Asian Pacific Association for the Study of the Liver treatment stopping rules (mean time, 164 ± 45 weeks) from January 2007 through June 2011 in Taiwan. Eighty-three were hepatitis B e antigen (HBeAg)-positive, and 169 were HBeAg-negative. Patients had regular post-treatment follow-up examinations for at least 12 months. Virologic relapse was defined on the basis of serum HBV DNA >2000 IU/mL after entecavir therapy. Clinical relapse was defined as a level of alanine aminotransferase > 2-fold the upper limit of normal and HBV DNA > 2000 IU/mL.

RESULTS

Two years after therapy ended, 42% of HBeAg-positive patients had a virologic relapse, and 37.6% had a clinical relapse; 3 years after therapy ended, these rates were 64.3% and 51.6% for HBeAg-negative patients, respectively. On the basis of Cox regression analysis, factors independently associated with virologic and clinical relapse included old age, HBV genotype C, and higher baseline levels of HBsAg for HBeAg-positive patients and old age and higher end-of-treatment levels of HBsAg for HBeAg-negative patients. In HBeAg-positive patients, risk of HBV relapse increased with age ≥ 40 years and HBsAg level ≥ 1000 IU/mL at baseline (P < .001). In HBeAg-negative patients, the combination of age (< 55 years) and HBsAg level (< 150 IU/mL) at the end of treatment was associated with a lower rate of virologic relapse (4.5% of HBeAg-negative patients had viral relapse at year 3). The decrease in level of HBsAg from month 12 of treatment until the end of treatment was greater in patients who did lose HBsAg after entecavir therapy compared with those who did not.

CONCLUSIONS

The combination of age and level of HBsAg is associated with relapse of HBV infection after treatment with entecavir. HBsAg levels might be used to guide the timing of cessation of entecavir treatment in patients with chronic HBV infection.

Combining age and HBsAg level predicts post-treatment durability of nucleos(t)ide analogue-induced HBeAg seroconversion

BACKGROUND AND AIMS

Previous studies have indicated that lamivudine-induced hepatitis B e antigen (HBeAg) seroconversion may not be durable in the Asian population. We investigated the useful predictors of post-treatment hepatitis B virus (HBV) relapse in patients with nucleos(t)ide analogue (NA)-induced HBeAg loss/seroconversion.

METHODS

A total of 157 non-cirrhotic patients with NA-induced HBeAg loss/seroconversion (78, lamivudine; 68, entecavir; 11, telbivudine) were retrospectively analyzed. All patients had at least 12 months of post-treatment follow-up and consolidation therapy duration.

RESULTS

The cumulative rate of post-treatment HBV relapse at 5 years was 57.1%. Multivariate analysis revealed that age and baseline hepatitis B surface antigen (HBsAg) levels independently predicted post-treatment HBV relapse. The post-treatment HBV relapse rate was significantly higher in patients aged > 40 years than in those < 40 years (P < 0.001). A baseline HBsAg level of 2000 IU/mL was the optimal cut-off value for predicting post-treatment HBV relapse (P = 0.002). The post-treatment HBV relapse risk further increased with the presence of both risk factors (age ≥ 40 years and baseline HBsAg level ≥ 2000 IU/mL; P < 0.001). A prolonged consolidation therapy period of ≥ 18 or 24 months had no positive effect on sustained viral suppression. There was no significant difference in post-treatment HBV relapse rates between patients with lamivudine- and entecavir-induced HBeAg loss/seroconversion during the off-treatment follow-up (P = 0.31).

CONCLUSION

The combination of an age of 40 years and a baseline HBsAg level of 2000 IU/mL was a useful marker for predicting post-treatment HBV relapse in patients with NA-induced HBeAg loss/seroconversion.

Serum hepatitis B surface antigen levels predict treatment response to nucleos(t)ide analogues

Quantification of hepatitis B surface antigen (HBsAg) has been suggested to be helpful in the management of chronic hepatitis B (CHB) patients. Nucleos(t)ide analogs (NAs) are the therapy of choice for CHB and are used in the majority of CHB patients. NAs are able to induce hepatitis B virus (HBV) viral suppression, normalization of alanine aminotransferase (ALT) levels, and improvement in liver histology. Automated quantitative assays for serum HBsAg have recently become available, facilitating standardized quantification of serum HBsAg. This has led to increased interest in the clinical application of quantitative serum HBsAg for predicting therapeutic response to NAs. Recent studies have shown that a decline in serum HBsAg levels in patients receiving peginterferon may signal successful induction of immune control over HBV, and can therefore be used to predict therapeutic response. NA treatment typically induces a less rapid decline in HBsAg than interferon treatment; it has been estimated that full HBsAg clearance can require decades of NA treatment. However, a rapid HBsAg decline during NA therapy may identify patients who will show clearance of HBsAg. Currently, there is no consensus on the clinical utility of serum HBsAg monitoring for evaluating patient responses to NA therapy. This review focuses on recent findings regarding the potential application of HBsAg quantification in the management of CHB patients receiving NA therapy.